From a065d786753b83ab92873b90d8d61d9fe5639fdd Mon Sep 17 00:00:00 2001 From: Damien George Date: Thu, 22 Jun 2017 16:28:07 +1000 Subject: drivers/onewire: Move onewire.py, ds18x20.py from esp8266 to drivers. These drivers can now be used by any port (so long as that port has the _onewire driver from extmod/modonewire.c). These drivers replace the existing 1-wire and DS18X20 drivers in the drivers/onewire directory. The existing ones were pyboard-specific and not very efficient nor minimal (although the 1-wire driver was written in pure Python it only worked at large enough CPU frequency). This commit brings backwards incompatible API changes to the existing 1-wire drivers. User code should be converted to use the new drivers, or check out the old version of the code and keep a local copy (it should continue to work unchanged). --- esp8266/modules/onewire.py | 91 ---------------------------------------------- 1 file changed, 91 deletions(-) delete mode 100644 esp8266/modules/onewire.py (limited to 'esp8266/modules/onewire.py') diff --git a/esp8266/modules/onewire.py b/esp8266/modules/onewire.py deleted file mode 100644 index 83318d1a47..0000000000 --- a/esp8266/modules/onewire.py +++ /dev/null @@ -1,91 +0,0 @@ -# 1-Wire driver for MicroPython on ESP8266 -# MIT license; Copyright (c) 2016 Damien P. George - -from micropython import const -import _onewire as _ow - -class OneWireError(Exception): - pass - -class OneWire: - SEARCH_ROM = const(0xf0) - MATCH_ROM = const(0x55) - SKIP_ROM = const(0xcc) - - def __init__(self, pin): - self.pin = pin - self.pin.init(pin.OPEN_DRAIN) - - def reset(self, required=False): - reset = _ow.reset(self.pin) - if required and not reset: - raise OneWireError - return reset - - def readbit(self): - return _ow.readbit(self.pin) - - def readbyte(self): - return _ow.readbyte(self.pin) - - def readinto(self, buf): - for i in range(len(buf)): - buf[i] = _ow.readbyte(self.pin) - - def writebit(self, value): - return _ow.writebit(self.pin, value) - - def writebyte(self, value): - return _ow.writebyte(self.pin, value) - - def write(self, buf): - for b in buf: - _ow.writebyte(self.pin, b) - - def select_rom(self, rom): - self.reset() - self.writebyte(MATCH_ROM) - self.write(rom) - - def scan(self): - devices = [] - diff = 65 - rom = False - for i in range(0xff): - rom, diff = self._search_rom(rom, diff) - if rom: - devices += [rom] - if diff == 0: - break - return devices - - def _search_rom(self, l_rom, diff): - if not self.reset(): - return None, 0 - self.writebyte(SEARCH_ROM) - if not l_rom: - l_rom = bytearray(8) - rom = bytearray(8) - next_diff = 0 - i = 64 - for byte in range(8): - r_b = 0 - for bit in range(8): - b = self.readbit() - if self.readbit(): - if b: # there are no devices or there is an error on the bus - return None, 0 - else: - if not b: # collision, two devices with different bit meaning - if diff > i or ((l_rom[byte] & (1 << bit)) and diff != i): - b = 1 - next_diff = i - self.writebit(b) - if b: - r_b |= 1 << bit - i -= 1 - rom[byte] = r_b - return rom, next_diff - - def crc8(self, data): - return _ow.crc8(data) -- cgit v1.2.3